33905021 has 4 divisors (see below), whose sum is σ = 35899452. Its totient is φ = 31910592.

The previous prime is 33905017. The next prime is 33905033. The reversal of 33905021 is 12050933.

It is a happy number.

33905021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21724921 + 12180100 = 4661^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 33905021 - 2² = 33905017 is a prime.

It is a super-2 number, since 2×33905021² = 2299100898020882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33905621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 997190 + ... + 997223.

It is an arithmetic number, because the mean of its divisors is an integer number (8974863).

Almost surely, 2^33905021 is an apocalyptic number.

It is an amenable number.

33905021 is a deficient number, since it is larger than the sum of its proper divisors (1994431).

33905021 is a wasteful number, since it uses less digits than its factorization.

33905021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1994430.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 33905021 is about 5822.8018169950. The cubic root of 33905021 is about 323.6592369413.

Adding to 33905021 its reverse (12050933), we get a palindrome (45955954).

The spelling of 33905021 in words is "thirty-three million, nine hundred five thousand, twenty-one".